Add new pipeline flow and refactor tests

What does this MR do?

This is part 2 of Create a flow for pipeline access. In this MR:

• Rename the wait methods under Page::Project::Pipeline::Index to help with readability
• Add a new flow to wait for a pipeline until it reaches a desired status
• Refactor tests accordingly

Closes https://gitlab.com/gitlab-org/quality/team-tasks/-/issues/709

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content